Transmission brake



May 18 1926.

1,585,082 M. CHAMBERLAIN TRANSMISSION BRAKE Filed August 29, 1925 INVENTOIE. Afar/vs tfiamber/a/y Patented May 18, 1 926 unfit-nu TRANSMISfiIGlI BRAKE.

' Application filed August 29, 1925.

This invention relates to the transmissions of Ford automobiles. In the Ford car, the transmission includes three bands, all of equal width and each of which cooperates with a drum. That is to say, thereis a reverse drum, a slow a pee rum nd 11 brake drum having bands cooperating ther with and all of the same width. To the rear of the brake drum, a driving plate is firmly aihxed.

It is well known to drivers of Ford cars 7 that the brake band will wear out in a much i the car and should not be attempted, except in cases of emergency. The factremains that when the car is used as intendech'the brake band willwear out long bei e the other bands are suiiicientl'y worn to w rant their replacemen and such band has to be rel'ined or the other bands must be employed for braking purposes.

With these considerations in mind, the object of the present invention is to provide a more reliable, substantial and durable brake than the stock brake or" the Ford transmission and to accomplish this result without appreciably changing the constructicn ofthe stock parts.

In practically carrying out the invention, I have discovered that this result may be accomplished by substituting for the driving; plate of the Ford transmission a combined supplemental brake drum and driving plate,

7 being of appreciable width.

the face of said supplemental brake drum The supplemental drum and brake drum are of the same diameter so that when they are secured together as'normal, their combined width will be considerably in excess of the braking surface afforded by the stock drum. A brake band of corresponding width cooperates with the brake drum and the braking surface of the supplemental drum and is suitably lined, so that the braking surr'ace thus atiorded by the addition of the peripheral surface of the supplemental drum will so distribute the wear as to minimize such Serial No. 53,288.

wear; in practice, I have found that when this invention is employed, in the normal manner, that brake bands will last as long as the slow speed and reverse bands, and, accordingly, the cost of replacements is mi'n imized' and the time incident to the making of frequent replacements as heretofore is saved.

l eaturcs'oi the invention, other than those specified, will be apparent from th hereinarlter detailed description and claims, when read in conjunction with the accompanying drawings.

The accompanying drawing illustrates one practical embodiment oi the invention, but

the construction therein shown is. to be understood as illustrative, only, and not as defining the limits o1 the invention.

.liigure 1 shows in perspective certain cooperating parts of Ford transmission mechanism having the resent invention incorporated therein. In this view, the driving plate is shown as removed from the brake drum in the interest oi clearness; and, l ig'urc 2' is a side elevation of the parts with the driving plate attached to the brake.

drum and in this view the bands and their linings are shown in section.

In: the showing of the drawings, 1 designates a fly wheel, 2 the reverse drum, 3. the

slow speed drum, 4 the brake drum, 5 the transmission shaft and 6 the main drive shaft. All these parts are the same as in the Ford stock car and do not embody the invention.

In accordance with Ford construction, the

driving plate is secured to the end of the main drive shaft 6 and is bolted to the brakeo rum. This plate is, in the stoclrcar, a thin plate having just sufiicient thickness to em body the necessary structural strength. In accordance with the present invention, in contra-distinction, the driving plate, which bears the reference character 7, is made with a relatively wide face shown in the drawings as almost halt as wide as the face or" the brake drum although, in practice, it may be made either wider or narrower than in the proportion stated.

The drive plate 7 has associated therewith the mechanical parts common to the stock Cal periphery of the brake drum, as clearly appears from Figure .1.

From this latter figure, it will be seen that the aggregate width of the driving plate 7 and brake drum 4, the faces of both of which constitute collectively a braking surface, is considerably greater than the face of either the slow speed drum 3 or the reverse drum 2. liioreover, there is, in the proportions shown, in the drawings, an increase of 50 percent in braking surface by the addition of the periphery of the driving plate to the brake drum. Bands 9 and 10 provided with suitable lining 11, cooperate with the two drums 2 and 3, but a relatively wide brake band 12 having correspondingly wide lining ll cooperates ith the drum 4 and plate 7.

In practice, the invention may he incorporated in a stock car by simply substituting the wide face driving plate and the wide face brake band 12 with its lining ll for the corresponding stock parts. This can be done in a few minutes. I he position of the clutch fingers with respect to the operating mechanism is not changed nor is the position of the brake pedal changed as the operating ears of the band 12 are in practice placed adjacent one edge of the band 12, as shown in dotted lines at 13 in Figure 2, so that they there occupy the position which they occupy in a stock car. It therefore follows that in adapting the invention to any steel: car of the make under consideration only two parts need to be changed and this is accomplished by simply taking out the stock uriving plate and brake band and substituting the plate and band of my invention.

The plate 7 is made of suiiicient width that it will constitute, in effect, a brake drum in itself and inasmuch as it preferably has a narrower face than the brake drum -l-, I prefer to term it a supplemental drum.

It will thus appear that in accordance with the present invention, the drive plate serves a dual purpose to which it has heretofore not been put, in that it not only serves its normal purpose of driving, but it 0011- stitutes in itself a supplemental brake drum. Year on the brake hand is minimized and inasmuch as the braking surface is greatly increased, the relining is not nearly so necessary at frequent intervals as was former the case. The present invention therefore produces marked economy and its installation is inexpensive.

Having thus fully described the invention, what I claim as new and desire to secure by Letters Patent is:

1. Transmission mechanism embodying a brake drum a reverse drum, a slow speed drum and a supplemental brake drum, all of which are coaxial and the latter of which also serves the purpose of a drive plate and is of the same diameter as the bralce drum and is secured thereto, a band cooperating with each of the reverse and low speed drums, and a single band collectively coopcrating with both the brake drum and the supplemental brake drum.

2. 'lransmission mechanism for Ford cars embodying a brake drum, a driving plate secured to the brake drum in alinemenl; therewith, said driving plate being of the une diameter as the brake drum and having a relatively wide surface forming a continuation of the surface of the brake drum, whereby said driving plate constitutes a supplemental brake drum, and a single brake band provided with a suitable lining simultaneously cooperating with both the brake drum and the supplemental brake drum.

3. Ford transmission mechanism embodying a brake drum, a supplemental brake drum positioned coaxially with the brake drum and secured thereto, a transmission shaft secured to the supplemental brake drum, clutch operating lingers also mounted on the supplemental brake drum, and a suit ably lined brake band common to both the brake drum and supplemental brake drum and simultaneously coopcrable with both.

In testimony whereof I have signed the foregoing specification.

MORRIS CHAMBERLAIN. 

